IT has come to our attention that the Vocational Training Council (VTC) has changed its requirements for appointment to lecturer (graduate), Technical Institutes, by reducing the years of post-degree working experience from six to three, apparently toencourage a better response to its recruitment exercise and to enlarge the selection pool. Whether such a change would achieve the result desired remains to be seen but, one thing is sure, good management requires that no one be made to feel discriminated against. In this case, our union expects the VTC to have considered compensating their old staff. But surprisingly, the VTC has decided that no salary revision can be given. To avoid the embarrassing situation of new staff with shorter or same years of working experience drawing a higher salary than old staff, the selection boards of various disciplines, so we are told, have been instructed that no applicants with more than four years working experience should be reco mmended for appointment. Such an operational manoeuvre is neither fair to their old staff or the members of the public. Nor is it helpful in ensuring the recruitment of the best calibre available. What's also worrying is that in the new rounds of recruitment exercise, ''Certificate of Education'' has been dropped as a qualification for salary calculations or as credentials in lieu of two years working experience. At a time when technical institutes have to take on more and more low-achievers as a result of the expansion of degree places in polytechnics and universities and the establishment of the two new technical colleges, the decision for such a change is indeed difficult to understand. LAW PING Secretary, Hong Kong Professional Teachers' Union.